分频技术在气层识别中的应用
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摘要
拟合追逐分解(MPD,Matching Pursuit Decomposition)法能提高地震数据谱分解的分辨率,使时间分辨率和频率分辨率保持一致,该方法避免了傅氏变换谱分解方法的时窗大小选择和分析时间点不准确的问题。含气地层对纵波资料产生较大的频率衰减,在储层下方可能出现低频强振幅的阴影区。而转换波资料受气藏影响小,在转换波剖面中不会出现同纵波类似的低频阴影区。因此,综合2种资料在分频剖面上的表现,可以进行储层含气性预测。对已知气藏的实际多波地震资料进行MPD分频处理,在不同波场的分频剖面上分析气层响应特征,可以找出含气地层在纵波和转换波分频剖面上的识别标志。
Spectral decomposition of PP-and PS-wave data using matching pursuit decomposition(MPD)has better resolution on both time and frequency,and maintains consistency across the entire time-frequency plane.Comparing to Fourier transform method,the MPD algorithm avoids choosing the size of window and dose not show temporal smearing of frequencies.PP-waves attenuate more than PS-waves when going through a gas reservoir,which gives rise to a noticeable low-frequency amplitude shadow on the PP-wave common frequency section beneath the gas reservoir.There exists no such a shadow on the PS-wave common frequency section.Thus we can predict gas-bearing potentials by investigating the behaviors of seismic waves on the both kinds of common frequency sections.The proposed method was verified on a real multi-component data set from northeaster China.
Spectral decomposition of PP-and PS-wave data using matching pursuit decomposition(MPD)has better resolution on both time and frequency,and maintains consistency across the entire time-frequency plane.Comparing to Fourier transform method,the MPD algorithm avoids choosing the size of window and dose not show temporal smearing of frequencies.PP-waves attenuate more than PS-waves when going through a gas reservoir,which gives rise to a noticeable low-frequency amplitude shadow on the PP-wave common frequency section beneath the gas reservoir.There exists no such a shadow on the PS-wave common frequency section.Thus we can predict gas-bearing potentials by investigating the behaviors of seismic waves on the both kinds of common frequency sections.The proposed method was verified on a real multi-component data set from northeaster China.
引文
1Chakrabrty A,Okaya D.Frequency-ti me decomposition of seismic data using wavelet-based methods[J].Geo-physics,1995,60(6):1906～1916
2Mallat S G,Zhang Zhifeng.Matching pursuit with ti me frequency dictionaries[J].IEEE Transactions on signal processing,1993,41:3397～3415
3王西文.地震资料处理和解释中的小波分析方法[M].北京:石油工业出版社,2004.130
4Castaqna J P,Sun Shengjie.Sieqfried R W.Instantane-ous spectral analysis:Detection of low-frequency shad-ows associated with hydrocarbons[J].The Leading Edge,2003,22(2):120～127
5Mitchell J T,Derzhi N,Lichma E,et al.Energy absorp-tion analysis:Acase study[J].Expanded Annual of66th Annual Internation SEG Meeting,1996,1785～1788
6Martin N W,Azavache A,Donati MS.Indirect oil de-tection by using P-wave attenuation analysis in Eastern Venezuela Basin[J].Expanded Abstracts of68thAnnu-al Internation SEG Meeting,1998,914～917
7黄中玉,王于静,苏永昌.一种新的地震波衰减分析方法——预测油气异常的有效工具[J].石油地球物理勘探,2000,35(6):768～773
8Chapman M,Liu Enru,Li Xiangyang.The influence of abnormally high attenuation on AVO signatures[J].The Leading Edge,2005,24(11):1120～1125
9Liu Enru,Chapman Mark,Loizou Nick,et al.Applica-tions of spectral decomposition for AVO analyses in the west of Shetland[J].Expanded Abstracts of76th Annual Internation SEG Meeting,2006,279～283
10Ebrom Dan.The low-frequency gas shadow on seismic sections[J].The Leading Edge,2004,23(8):772
2Mallat S G,Zhang Zhifeng.Matching pursuit with ti me frequency dictionaries[J].IEEE Transactions on signal processing,1993,41:3397～3415
3王西文.地震资料处理和解释中的小波分析方法[M].北京:石油工业出版社,2004.130
4Castaqna J P,Sun Shengjie.Sieqfried R W.Instantane-ous spectral analysis:Detection of low-frequency shad-ows associated with hydrocarbons[J].The Leading Edge,2003,22(2):120～127
5Mitchell J T,Derzhi N,Lichma E,et al.Energy absorp-tion analysis:Acase study[J].Expanded Annual of66th Annual Internation SEG Meeting,1996,1785～1788
6Martin N W,Azavache A,Donati MS.Indirect oil de-tection by using P-wave attenuation analysis in Eastern Venezuela Basin[J].Expanded Abstracts of68thAnnu-al Internation SEG Meeting,1998,914～917
7黄中玉,王于静,苏永昌.一种新的地震波衰减分析方法——预测油气异常的有效工具[J].石油地球物理勘探,2000,35(6):768～773
8Chapman M,Liu Enru,Li Xiangyang.The influence of abnormally high attenuation on AVO signatures[J].The Leading Edge,2005,24(11):1120～1125
9Liu Enru,Chapman Mark,Loizou Nick,et al.Applica-tions of spectral decomposition for AVO analyses in the west of Shetland[J].Expanded Abstracts of76th Annual Internation SEG Meeting,2006,279～283
10Ebrom Dan.The low-frequency gas shadow on seismic sections[J].The Leading Edge,2004,23(8):772
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